Cirrus down in SC

like this

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that was Stan Fox's crash at Indy in 1995. I remember seeing that picture on the front page of the paper. quite extreme...amazingly he lived but never really got over the injuries
 
Are Maserati, et al held to that same test?

SteveinMichigan said:
Exactly what I was thinking. I mean the company has already demonstrated a blatant disregard for the safety issues and continued to market the aircraft to persons who have no business flying it. Should we expect anything but more of that from the rank and file sales person?
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As far as the marketing standards, etc....I agree it's a double standard but once again, let's stay focused on the issue at hand.

So far as I am aware they have to pass crash tests to be declared roadworthy. I don't really understand the automotive side of things all that well beyond the basics since it's not my area of interest.
 
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Based on that, I assume the aircraft manufacturers are still required to demonstrate that their products are airworthy. Last I heard, Cirrus even went a step farther and required type-specific training for pilots who purchased their airplanes.

Are you suggesting their marketing methods are unscrupulous, underhanded, illegal, unethical or in any way skirting what's right?



SteveinMichigan said:
As far as the marketing standards, etc....I agree it's a double standard but once again, let's stay focused on the issue at hand.

So far as I am aware they have to pass crash tests to be declared roadworthy. I don't really understand the automotive side of things all that well beyond the basics since it's not my area of interest.
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dmccormack said:
Of course IndyCar drivers wear NOMEX suits, boots, gloves, helmets, and flameproof balaclavas.

I doubt many passengers would enjoy suiting up that way.

:dunno:
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Geesh Dan, if passengers were going to wear all of that, why not add bubble wrap <g>. Several layers would absorb the shock and if they got ejected from the cockpit, they could go pop, pop, pop all they way down the runway :goofy:

Best,

Dave
 
All of that gear doesn't keep the body in one piece, though. It helps in a fire, but the car itself is the best protection for the driver.
 
I have not read this entire thread, this may have already been brought up. I started a thread a few months ago about joy stick vs. yoke or stick flight controls. I am wondering if, under extreme stress situations, such as this fellow was in, if he could have been applying somewhat more aileron and elevator control than was needed?

A stick or yoke requires a whole lot more movement than a joy stick does for pitch and bank maneuvers, I would think. I've never used a joy stick, so I'm asking what y'all think?

John
 
jesse said:
An airplane isn't a car ... and well... pulling the chute too low could be pretty disastrous.
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I think with enough forward airspeed, the lower altitude isn't too big of a deal. They had to be able to enter a spin, let it go 1 turn/3 seconds, then pull the chute, and have the chute fully inflated, all in less than 1000 feet. (Maybe it was a "did" and not a "had to", it's been a long time since I talked to the test pilot that did it.) Since the spin has little or no forward airspeed, I would think that the forward airspeed in a more normal flight regime would allow the chute to inflate in a lot less vertical space.

SteveinMichigan said:
That's the problem: the residual structure is what protects the occupants. Granted a lot of metal aircraft out there don't do an ideal job of it, but composites fail upon impact rather than deforming which gives ZERO occupant protection
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Incorrect. Deformation of metal and shattering of composites both require energy to happen, thus either one is absorbing energy. Just because the composite ends up in a zillion little pieces doesn't mean it didn't provide any protection during the breaking process.

which may explain why you seldom see survivors in crashes of composite aircraft where as it is far more common to see non-fatal crashes (even if you exclude "non-crashes" like runway overruns, hard landings, etc) in aircraft built of more traditional materials.
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Is it composite aircraft, or Cirrus? Like I noted above, Diamonds have an excellent safety record with only one fatal crash. Even the guy that accidentally flew into terrain while looking at an elk, all aboard survived.

We technically don't know that so let's not make assumptions based on facts not in evidence, OK?
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Like the rest of the thread, including parts of your posts? :rolleyes:

Exactly what I was thinking. I mean the company has already demonstrated a blatant disregard for the safety issues
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I don't buy that at all. I don't disagree with any of what you've found through your research, and I'm sure they could do more to protect occupants in a crash, but they've focused a lot more effort on trying to make sure crashes don't happen in the first place. To say that they demonstrate a blatant disregard of safety issues only shows that you don't have a good grasp of their corporate philosophy.

and continued to market the aircraft to persons who have no business flying it.
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Bull****. I've said it before and I'll say it again. There is ABSOLUTELY NOTHING WRONG with marketing the Cirri to anyone, and there is nothing wrong with learning to fly in a Cirrus, even an SR22, especially if that's what you're going to be flying.

You know what I'd really like to see? An analysis of how the Cirrus accident pilots were trained. There's two ways to get out on your own in an SR22: A) You can train in a 172, take your checkride after having mastered the easy bird, buy a Cirrus, get 5 hours of dual in the Cirrus to obtain your HP endorsement and make the insurance company happy, and off you go.

Or, B) you can buy the SR22 right out of the gate, and you'll have to spend a lot more time training to be able to pass the PTS in this faster bird, but when you have your ticket you'll know the Cirrus REALLY well.

I'd be willing to bet money that most of the Cirrus accident pilots chose option "A" and would have done better had they learned to fly in the Cirrus.
 
John Baker said:
I have not read this entire thread, this may have already been brought up. I started a thread a few months ago about joy stick vs. yoke or stick flight controls. I am wondering if, under extreme stress situations, such as this fellow was in, if he could have been applying somewhat more aileron and elevator control than was needed?

A stick or yoke requires a whole lot more movement than a joy stick does for pitch and bank maneuvers, I would think. I've never used a joy stick, so I'm asking what y'all think?
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I assume by "joy stick" you mean the Cirrus' side yoke. And yes it's a "side yoke" not a "side stick" - Fly a Cirrus and then a Columbia and you'll see the difference. (The side yoke slides in and out of the panel like a regular Cessna/Cherokee yoke, the side stick rotates fore and aft.)

Really, it's an airplane-by-airplane comparison of flight characteristics more so than what the flight controls are that matters. For example, both a Piper Cub and an Extra 300 have center sticks, but if you take the control input that you use to bank in a turn in the Cub and use it in the Extra, you will have rolled twice before you have a chance to scream. (In delight or terror depends on whether you knew that already. :D)

Personally, I found the Cirrus side yoke pretty easy to get used to - Took all of about 20 seconds before I completely forgot I wasn't using a regular ram's horn yoke.
 
Deformation of metal and shattering of composites both require energy to happen, thus either one is absorbing energy. Just because the composite ends up in a zillion little pieces doesn't mean it didn't provide any protection during the breaking process.
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True, but I was pointing out that once it shatters, whatever is behind it (such as a pilot) is going to be more or less exposed to the ground, trees, etc which is not the case nearly as often in non-composite aircraft. It like comparing a bumper and a windshield: both will absorb force, but once the windshield shatters it's not going to do a whole hell of a lot for the rest of the crash sequence except potentially become flying debris.

A) You can train in a 172, take your checkride after having mastered the easy bird, buy a Cirrus, get 5 hours of dual in the Cirrus to obtain your HP endorsement and make the insurance company happy, and off you go.
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That's part of the problem: turning them loose with minimal transition training. The same problem has arisen again and again both in civilian and military training programs so this is not an unique situation by any stretch. I'm not so sure the Cirrus from the word "go" idea is a good one but if you can provide evidence that it reduces the crash rate after training and that the crash rate during training is lower, you'll have my support on that one. Until you or someone else with the inclination puts forth the credible evidence you seek, your stance that there is nothing wrong with marketing the Cirrus line to the affluent and often cock sure section of our society is no more valid than my assessment (and that of many others, although you know what they say about what everyone agreeing can mean ;) ) that it's a bad idea to encourage a low hour pilot to fly an unforgiving high performance aircraft.

I'd be willing to bet money that most of the Cirrus accident pilots chose option "A" and would have done better had they learned to fly in the Cirrus.
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....or the training fatality rate could spike which seems to be more of the case based on the available evidence. Like I said, I'm only looking to find out the truth and we do that best by pulling together the evidence and then tearing it- and the ideas each side has about it- apart. If you can prove my suppositions incorrect, more power to you and I'll buy you a beer (or burger or whatever) either way to celebrate the day we have the data to use in determining which one of us is closer to correct.

Not to start a debate but I have an interesting academic question to pose: Suppose you find credible evidence that starting people out in Cirrus SR22s from the get-go actually makes them safer in operating them. Would that not raise the question of where do you cut off the "Oh, I'm going to fly higher performance singles" exception to training. I mean if I were to go out and buy a Pilatus or a Mooney or a V-tail Bonanza because that's what I want to fly would you think it's a good idea for me to start out in one of those? What if I hit the lottery and decided to buy a P-51?
 
SteveinMichigan said:
True, but I was pointing out that once it shatters, whatever is behind it (such as a pilot) is going to be more or less exposed to the ground, trees, etc which is not the case nearly as often in non-composite aircraft. It like comparing a bumper and a windshield: both will absorb force, but once the windshield shatters it's not going to do a whole hell of a lot for the rest of the crash sequence except potentially become flying debris.
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It's hard to speculate without much reliable data but I'd be surprised if the Cirrus "roll cage" would disintegrate in what would be a survivable crash if that cage were made of steel tubing of equal strength. I've seen several fiberglass boats that "disintegrated" in a high energy collision and generally it was the "skin" that turned to dust while the stringers and other structural components remained relatively intact. I'd bet that the same is true of fiberglass wing spars.
your stance that there is nothing wrong with marketing the Cirrus line to the affluent and often cock sure section of our society is no more valid than my assessment (and that of many others, although you know what they say about what everyone agreeing can mean ;) ) that it's a bad idea to encourage a low hour pilot to fly an unforgiving high performance aircraft.
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It seems to me that virtually every manufacturer of "high performance" airplanes markets them to the "affluent and often cock sure" crowd. They'd be fools not to since those folks are the only ones with the cash to spend on a $500k-$1MM airplane for personal use. Cirrus has just managed to be better at this but at the same time they've gone much further than any other manufacturer regarding training programs and other preventative safety measures IMO.
Not to start a debate but I have an interesting academic question to pose: Suppose you find credible evidence that starting people out in Cirrus SR22s from the get-go actually makes them safer in operating them. Would that not raise the question of where do you cut off the "Oh, I'm going to fly higher performance singles" exception to training. I mean if I were to go out and buy a Pilatus or a Mooney or a V-tail Bonanza because that's what I want to fly would you think it's a good idea for me to start out in one of those? What if I hit the lottery and decided to buy a P-51?
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I've known several pilots who pretty much started their training in a high performance single like a Bonanza, Cirrus, or Mooney and many (but not all) of them managed to become safe pilots. The difference between the good ones and the bad ones seems to be more judgment related than anything else. I've also flown with a number of pilots with lots of pilot time in such airplanes that scare me either from lack of judgment, basic skills, or both. And while I don't know anyone who started in a PC-12, the one Pilatus owner/pilot I know says it's easier to fly than the Bonanza he had before. Yes there are lots of advanced systems and it lands pretty hot without flaps but it might not be any more demanding of basic pilot skills than other high performance singles. As to the P-51 notion, given the design goals and ancient design methods involved I'd have to say that's a completely different kettle of worms. But I don't think that this is because a pilot couldn't be trained to fly one from the get go, but rather that I don't think any instructors would be willing and or able to teach basic skills in such a difficult airplane to fly.

What I really don't get is the notion that a SR-22 is especially hard to master. Yes it lands faster than a 172, and has a bigger engine but it's not like a snake ready to strike a hapless pilot for the slightest transgression. Heck an AT-6 (SN-J) is a lot more cantankerous yet plenty of military pilots have managed to learn to fly in one.

I also don't see much in the way of trends that indicate the cause of most Cirrus accidents are pilot's unable to control their airplanes under normal circumstances. Attempting the "impossible turn" has done in lots of pilots of lesser airplanes as has flying into weather beyond the pilot's skill level. I suspect that more than anything else the one thing responsible for the apparent high rate of Cirri accidents is the large number of them flying combined with their typical mission of cross country flying.
 
If overselling based on pilot capabilities was a crime, Beech would have been out of business before 1948. Under-trained, under-prepared and incompetent pilots need only a logbook and a checkbook (not necessarily in that order) and they are good to go.

flyingcheesehead said:
Bull****. I've said it before and I'll say it again. There is ABSOLUTELY NOTHING WRONG with marketing the Cirri to anyone, and there is nothing wrong with learning to fly in a Cirrus, even an SR22, especially if that's what you're going to be flying.

You know what I'd really like to see? An analysis of how the Cirrus accident pilots were trained. There's two ways to get out on your own in an SR22: A) You can train in a 172, take your checkride after having mastered the easy bird, buy a Cirrus, get 5 hours of dual in the Cirrus to obtain your HP endorsement and make the insurance company happy, and off you go.

Or, B) you can buy the SR22 right out of the gate, and you'll have to spend a lot more time training to be able to pass the PTS in this faster bird, but when you have your ticket you'll know the Cirrus REALLY well.

I'd be willing to bet money that most of the Cirrus accident pilots chose option "A" and would have done better had they learned to fly in the Cirrus.
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Yet again, personal responsibility is thrown out the window.
 
nddons said:
Interestingly, I got a call from a Cirrus salesman this morning (one of the benefits of sitting in Cirri and leaving your name with the salesmen at AirVenture.) I asked about this accident, which he knew about, and which he saw the pictures of. I asked about crashworthyness of the composites, and he mentioned that Cirrus has a roll cage around the cabin....
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None visible in this photo of the first production Cirrus crash:

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However, this Cirrus Web Page says it's got a "3-G Roll Cage."

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Perhaps it was added later....

Ron Wanttaja
 
SteveinMichigan said:
I'm not so sure the Cirrus from the word "go" idea is a good one but if you can provide evidence that it reduces the crash rate after training and that the crash rate during training is lower, you'll have my support on that one.
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Unfortunately, the NTSB does not provide us with enough info to make that determination one way or the other. :dunno:

Until you or someone else with the inclination puts forth the credible evidence you seek, your stance that there is nothing wrong with marketing the Cirrus line to the affluent and often cock sure section of our society is no more valid than my assessment (and that of many others, although you know what they say about what everyone agreeing can mean ;) ) that it's a bad idea to encourage a low hour pilot to fly an unforgiving high performance aircraft.
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Have you ever flown a Cirrus? I wouldn't call it unforgiving. :no: It really is a good airplane - The most "unforgiving" thing about it is that it goes fast (which can be remedied by pulling the throttle back when the plane starts to catch up to you) and it lands fairly fast. It is not difficult to fly by any stretch of the imagination. :no:

Either way, Cirrus is doing what they can do to expand the pilot population, and I give them major kudos for that. It's smart marketing, and it certainly puts a lot of money in their coffers, but it helps the rest of GA out in the process. I really don't think there's anything wrong with someone buying an SR22 and learning to fly in it, especially if they use the Cirrus Access program - In fact, ALL GA manufacturers should have marketing like Cirrus and training programs like Cirrus Access. It fixes a lot of the current problems with flight training.

....or the training fatality rate could spike which seems to be more of the case based on the available evidence.
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How many Cirrus accidents have been training flights? I don't recall any right offhand (I'm sure there have been some, but I don't think it's a "spike" or even out of line with training in other manufacturers' airplanes).

If you can prove my suppositions incorrect, more power to you and I'll buy you a beer (or burger or whatever) either way to celebrate the day we have the data to use in determining which one of us is closer to correct.
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That's kind of the problem - That sort of data isn't included in NTSB reports which makes it somewhat difficult to analyze these issues. :(

Not to start a debate but I have an interesting academic question to pose: Suppose you find credible evidence that starting people out in Cirrus SR22s from the get-go actually makes them safer in operating them. Would that not raise the question of where do you cut off the "Oh, I'm going to fly higher performance singles" exception to training. I mean if I were to go out and buy a Pilatus or a Mooney or a V-tail Bonanza because that's what I want to fly would you think it's a good idea for me to start out in one of those? What if I hit the lottery and decided to buy a P-51?
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People with a lot of money have learned to fly successfully in crazier airplanes than on your list (well, except for maybe the P-51). Where the line needs to be drawn varies greatly with different people. There's people that probably shouldn't even learn to fly in a C172, yet there are others who have been able to learn in such airplanes as a Learjet (IIRC someone has posted here before who it was and what exact type, I can't remember offhand).
 
I might point out that as a military pilot, we were flying turbine helicopters on combat missions in very demanding circumstance with under 250 hours of flying time. Military flight school was 220 total hours back when I attended. We did start with piston helos when I attended; took our instrument training in pistons; then moved to the UH-1 which was a pretty sophisticated turbine at the time. I also took about 20 hours of Cobra training and flew those.

Civil training is certainly different, but to make an argument that one can't be trained to fly sophisticated aircraft in a couple hundred hours is a debate you would lose with virtually any pilot that took military flight training.

Best,

Dave
 
Kent: The fellas that flew P-51s in WWII started in the T-6 IIRC and were in the 51s in a pretty short period of time.

We might ask if anyone knows one of these folks and can ask. I'm pretty sure that's what more than one fella that flew those told me. Many flew the 51 solo first flight as there weren't a lot of two place birds around (P-51s that is).

I know things have changed a lot, but is boosts the argument it can be done. I'm sure there were higher accident rates. What seems to have changed is our acceptance of accidents. Of course, in time of war it changes, but rates are pretty low today compared to some past periods. The Cirri get a lot of attention because they are expensive GA aircraft, the pilots are usually well known, and the crashes often occur in someone's neighborhood.

Best,

Dave
 
My uncle Jim Gardner who still lives in COS started on the PT-6, then first combat was P-40 with later transition to Mustangs. He said the guy doing the checkout just stood on the wing and pointed at stuff, answered questions for a while and they you went flying by yourself. No big deal according to him, they were all pretty much the same. Even the German airplanes they captured and flew for tactical insights.

Dave Siciliano said:
Kent: The fellas that flew P-51s in WWII started in the T-6 IIRC and were in the 51s in a pretty short period of time.

We might ask if anyone knows one of these folks and can ask. I'm pretty sure that's what more than one fella that flew those told me. Many flew the 51 solo first flight as there weren't a lot of two place birds around (P-51s that is).

I know things have changed a lot, but is boosts the argument it can be done. I'm sure there were higher accident rates. What seems to have changed is our acceptance of accidents. Of course, in time of war it changes, but rates are pretty low today compared to some past periods. The Cirri get a lot of attention because they are expensive GA aircraft, the pilots are usually well known, and the crashes often occur in someone's neighborhood.

Best,

Dave
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Dave Siciliano said:
Kent: The fellas that flew P-51s in WWII started in the T-6 IIRC and were in the 51s in a pretty short period of time.
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Yep - But nobody started in the -51.

A few months ago I attended a presentation by a WWII B-17 pilot. They had a whopping 65 hours of flight time, first in a single-engine trainer, then a twin-engine trainer (that had very poor flight characteristics), and a quickie checkout in the B-17, before they were handed a brand-new B-17 to ferry across the pond. :eek:

When they were out over the ocean, flying along at 10,000 feet, they started picking up ice. Having never been taught anything about airframe icing or what to do, they kept motoring along, until they could no longer maintain altitude. They went all the way down until they were basically in ground effect before they could maintain altitude, and the salt spray off the ocean melted the ice off the plane. :hairraise: He said that something like 45 new B-17 crews were making the trip across the pond at the time, and that over 2/3 of them never made it. :(
 
Uncle Jim said the Mustang was much easier to fly than the T-6. The standing joke was that it should have been the trainer.

flyingcheesehead said:
Yep - But nobody started in the -51.

A few months ago I attended a presentation by a WWII B-17 pilot. They had a whopping 65 hours of flight time, first in a single-engine trainer, then a twin-engine trainer (that had very poor flight characteristics), and a quickie checkout in the B-17, before they were handed a brand-new B-17 to ferry across the pond. :eek:

When they were out over the ocean, flying along at 10,000 feet, they started picking up ice. Having never been taught anything about airframe icing or what to do, they kept motoring along, until they could no longer maintain altitude. They went all the way down until they were basically in ground effect before they could maintain altitude, and the salt spray off the ocean melted the ice off the plane. :hairraise: He said that something like 45 new B-17 crews were making the trip across the pond at the time, and that over 2/3 of them never made it. :(
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Unfortunately, the NTSB does not provide us with enough info to make that determination one way or the other.
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I know....at least the readily available stuff is not much help. I put a couple of calls in to see if there is anything they are not publicizing and we'll see what sort of response I get back.

Isn't it lying on the ground next to the plane?
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That appears to be the windscreen with possibly the front part of the "roll cage" attached to its rear aspect. Regardless, the idea of having a "half cage" attached to frangible material as occupant protection and painting it to be the equivalent of a metal full protective cage is laughable.

and that over 2/3 of them never made it
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I doubt it was two-thirds. The loss records of military aircraft are pretty easily accessible (I've spent a fair amount of time digging around in them since I have an interest in aviation archaeology). Keep in mind that a significant number of B-17s survived the war to be melted into scrap and over 1/3 (4570 out of 12731 built) were lost in combat so I think a two-thirds loss in transit is a hyperbolic comment that overplays the very real dangers those crews faced on a ferry flight across the Atlantic.

Have you ever flown a Cirrus? I wouldn't call it unforgiving.
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Yeah, I've flown a couple of hours with an instructor at the airport next door after I got into a debate on the subject with him. It's a lot....how to phrase it "lighter touch" (?) than other aircraft. It's a good airplane- so long as you fly it the way it should be flown and have the maturity and experience to know to respect it's limitations- but at the same time, I realize that putting a faster aircraft in the hands of a low hour pilot who may lack that maturity and experience to be able to pull the throttle back, as you say, so the plane doesn't get ahead of them is a bad idea. My main concern with the Cirrus is not it's handling characteristics, but with how it reacts in a crash. I freely admit that most of the crashes (in fact, damn near all of them) have been the result of pilot error and poor judgment.

Where the idea that I fault the aircraft itself comes from is that firstly, the solution to the documented spin/stall issue was not to fix the aircraft but to put a rocket-launched parachute on the plane and secondly to market the aircraft as equivalent to a Cessna single engine for training and operations purposes (I've heard it come out of the mouths of Cirrus representatives in person and seem to recall that the claim was even made in one of the Cirrus ads a couple of years back...I'll see if I can find it again).

No big deal according to him, they were all pretty much the same.
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No offense intended, and I've heard it before from my friends who were pilots during WWII but that sentiment reeks of hindsight bias. If that was truly the case why was the mortality rate so freaking high during training? If there weren't serious problems with the approach they were using why did so many pilots die during initial and transition training (the number has been variously stated as between 13,000 and 15,000; or roughly 15% of the total US Army Air Force losses in the entire war)?
 
wabower said:
Uncle Jim said the Mustang was much easier to fly than the T-6. The standing joke was that it should have been the trainer.
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Just as a data point, the first time my dad manipulated the controls of an aircraft in flight was in an A-26 flying over occupied Germany after the war. Dunno if he ever did a landing or takeoff... (he was a crew chief)
 
Capt. Geoffrey Thorpe said:
Just as a data point, the first time my dad manipulated the controls of an aircraft in flight was in an A-26 flying over occupied Germany after the war. Dunno if he ever did a landing or takeoff... (he was a crew chief)
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Oh no...

Can you imagine?

"Go ahead -- the war's over -- what could hap --- OH NO!"
 
The quoted web page doesn't compare it to anything. It just says it's a 3g cage. Is that enough? What are the ratings of the other cages?

SteveinMichigan said:
That appears to be the windscreen with possibly the front part of the "roll cage" attached to its rear aspect. Regardless, the idea of having a "half cage" attached to frangible material as occupant protection and painting it to be the equivalent of a metal full protective cage is laughable.
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It just says it's a 3g cage
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When I asked a Cirrus rep, he said it is "rated to 3 g" as in the acceleration due to the force of gravity (the common usage of g, at least outside of the ghetto). He didn't seem to know much more about it and he really didn't like that I pointed out (in front of a bunch of potential customers) of a group that 3 g is a very low force. As one of my biomedical engineering professors pointed out, if you slam hard on your brakes at highway speed you'll experience around that that during a maximal deceleration stop.

Three g is not a terribly high impact force. Hell, prior to the experiments by Stapp and his colleagues, the assumption was that the human body could not routinely survive a deceleration of greater than 18 g. This mistaken belief had a lot to do with how the restraints used in the early years fared and how the integrity of the surrounding cockpit/passenger compartment was maintained (or rather, was not). There is a reason why the FAA started mandating 16 g rated seats in airliners which is an improvement of the 1950s standard 9 g seat that predated them.

I would like to point out that it's not uncommon at all to see survivable car crashes running somewhere around 20-25 g, especially with a young occupant who is properly restrained. If you get really hardcore about impact dynamics, take a look at some of the NASCAR data where impacts of 50-100 g happen with regularity and the roll cage holds up. Not ideally applicable for aircraft due to weight restrictions, but it makes the idea of a 3 g case as "protection" seem laughable. The research of Dr. Stapp and his team showed that aircrew can routinely survive decelerations of 32 g (that's about 315 m/s squared, for those of you who are paying attention to the physics involved) if the seat remains attached and the restraints do not fail. One or both of these contingencies fail to occur in a lot of crashes (both of Cirri and other aircraft as well). This is one of the reasons why having such a low standard for failure of a protective mechanism is, not to point to fine of a point on it, just plain stupid especially if you're going to use it to tout the safety of your aircraft in a crash.
 
SteveinMichigan said:
When I asked a Cirrus rep, he said it is "rated to 3 g" as in the acceleration due to the force of gravity (the common usage of g, at least outside of the ghetto). He didn't seem to know much more about it and he really didn't like that I pointed out (in front of a bunch of potential customers) of a group that 3 g is a very low force. As one of my biomedical engineering professors pointed out, if you slam hard on your brakes at highway speed you'll experience around that that during a maximal deceleration stop.

Three g is not a terribly high impact force. Hell, prior to the experiments by Stapp and his colleagues, the assumption was that the human body could not routinely survive a deceleration of greater than 18 g. This mistaken belief had a lot to do with how the restraints used in the early years fared and how the integrity of the surrounding cockpit/passenger compartment was maintained (or rather, was not). There is a reason why the FAA started mandating 16 g rated seats in airliners which is an improvement of the 1950s standard 9 g seat that predated them.

I would like to point out that it's not uncommon at all to see survivable car crashes running somewhere around 20-25 g, especially with a young occupant who is properly restrained. If you get really hardcore about impact dynamics, take a look at some of the NASCAR data where impacts of 50-100 g happen with regularity and the roll cage holds up. Not ideally applicable for aircraft due to weight restrictions, but it makes the idea of a 3 g case as "protection" seem laughable. The research of Dr. Stapp and his team showed that aircrew can routinely survive decelerations of 32 g (that's about 315 m/s squared, for those of you who are paying attention to the physics involved) if the seat remains attached and the restraints do not fail. One or both of these contingencies fail to occur in a lot of crashes (both of Cirri and other aircraft as well). This is one of the reasons why having such a low standard for failure of a protective mechanism is, not to point to fine of a point on it, just plain stupid especially if you're going to use it to tout the safety of your aircraft in a crash.
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Is there any chance that the roll cage is there to prevent death in case of accidental flip over accidents? For example, landing on grass and snagging the nosewheel in a gopher hole?

In that case, 3 Gs is probably plenty.
 
Is there any chance that the roll cage is there to prevent death in case of accidental flip over accidents? For example, landing on grass and snagging the nosewheel in a gopher hole?

In that case, 3 Gs is probably plenty.
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That's what I originally suspected (and agree that it would be potentially useful for that purpose) but according to two different reps I've talked to, they are playing it as a safety feature in "crashes" not noseovers.
 
SteveinMichigan said:
That's what I originally suspected (and agree that it would be potentially useful for that purpose) but according to two different reps I've talked to, they are playing it as a safety feature in "crashes" not noseovers.
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I would say there are "crash" scenarios that result in the airplane ending up on its back.
 
I would say there are "crash" scenarios that result in the airplane ending up on its back.
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Most of those are going to involve an impact to the roof of >3 g. About the only one I can think of that would not exceed that would be a slow (relatively speaking) noseover from putting the nose of the aircraft down an incline or into a ditch.
 
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